This invention relates to an improved construction and method for joining a part fabricated of metal to a part fabricated of thermo-insulating material, having a particularly advantageous application in the construction industry.
It further relates to providing a composite profile of two parts of metal joined in an improved manner by a bar, plate or strip of a relatively rigid thermo-plastic insulating material wherein the joined portion(s) of the plastic part is anchored in a groove defined in connection with, and extending longitudinally of, a metal part, the bounding wall surfaces of which groove are distinguished, at least in part, by knurling.
The invention has particular importance and significance in its application to the fabrication of frames and sashes for insulating windows and other elements of construction such as door frames. It should be understood, however, that the application of the construction and the method of the invention are not so limited.
Underlying the invention is the problem of effectively increasing the strength and reliability of the connection of parts of metal and thermo-insulating material in a composite profile and increasing in particular the shear strength between such parts.
To the extent known by those substantively involved in the present disclosure, the state of the prior art is best represented by U.S. Pat. No. 3,579,724 dated May 25, 1979, which issued in the name of Louis Toth. The structure and concept of this patent, however, does not evidence any specific pertinence to the points of novelty of the present invention.